March is transition season for weather

Posted: 5:17 PM, Mar 06, 2020
Updated: 2020-03-06 19:17:38-05
March Climate Chart
EF Tornado Scale

March is here and that means transition time when we’re talking weather. March is when the atmosphere is transitioning from winter to spring and this can result in quite the roller coaster ride of weather!

Cold air masses clash with warm air masses and result in wild temperature swings in a short amount of time. These wild temperature swings can also bring severe weather to areas east of the Rockies and stormy weather to the Southwest.

March Climate Chart

With the arrival of March, severe weather season also arrives from the Central Plains into the Gulf Coast. The clash between dry, cold winter air masses and the surge of warm, moist air masses often causes widespread violent weather including severe thunderstorms, hail, damaging wind and tornadoes. Unfortunately, as we witnessed earlier this week, Tennessee was ravaged by severe weather.

There are some incredible statistics coming in from scientists who are evaluating the damage caused by the tornado in Tennessee. The saddest statistic is that at least 24 lives were lost during this latest tornado outbreak.

According to the National Weather Service in Nashville, damage from the Nashville tornado indicates it was an EF-3 tornado that remained on the ground for just over 50 miles! The 50.2 mile long path is the third longest path of a tornado to remain on the ground in Tennessee history.

Only two other tornadoes have remained on the ground for a longer distance in the state. The longest, a devastating F5 tornado that stayed on the ground for 64.9 miles on April 16, 1998. The second longest, a tornado that remained on the ground for just a slightly longer distance than the one earlier this week. An F4 that cut a 50.9 mile path of destruction on May 7, 1971.

EF Tornado Scale
EF Tornado Scale

Fortunately, in the Southwest, our transition from winter to spring doesn’t include such violent weather. However, the transition can bring everything from rain, thunderstorms, wind, dust storms, high fire danger and even the occasional snowfall. In Tucson, we gain an hour of daylight during the month of March. This added daylight gives our temperatures a boost! Average daily highs climb from the lower 70s to start the month, all the way to the upper 70s to end the month.

Even though temperatures are getting warmer, winter still likes to remind us that it’s here until the Vernal equinox on the 21st of the month. In March, we’re still not without risk of getting another freeze. In Tucson, the average last freeze occurs March 3.

However, the latest last freeze to ever occur was May 3, 1899! You may want to keep those frost cloths handy for a few more weeks. March has brought snow to Tucson on several occasions over the years. The last time we saw a March snowfall, in Tucson, was when we received a trace on March 30, 1998. The largest March snowfall occurred on March 12, 1922, when 6 inches fell on the Old Pueblo.

This year, the climate prediction outlooks are calling for above average temperatures and below average rainfall. Only time will tell, so lets just enjoy the transition season roller coaster ride!